Abstract :
The main recent evolutions of microwaves devices (MESFET, MODFET, HBT, MISFET, IMPATT diodes and TED) are presented. It appears that many new physical phenomena must be taken into account when we want to describe the behaviour of such devices and to simulate them. These effects occur not only in bulk materials but also in heterostructures. Three different types of models are presented: Monte Carlo simulation, two dimensional and one dimensional resolution of basic equations. Their respective advantages are precised.
